1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2016-2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * Authors: Christian König, Felix Kuehling
24  */
25 
26 #include "amdgpu.h"
27 
28 static inline struct amdgpu_preempt_mgr *
29 to_preempt_mgr(struct ttm_resource_manager *man)
30 {
31 	return container_of(man, struct amdgpu_preempt_mgr, manager);
32 }
33 
34 /**
35  * DOC: mem_info_preempt_used
36  *
37  * The amdgpu driver provides a sysfs API for reporting current total amount of
38  * used preemptible memory.
39  * The file mem_info_preempt_used is used for this, and returns the current
40  * used size of the preemptible block, in bytes
41  */
42 static ssize_t mem_info_preempt_used_show(struct device *dev,
43 					  struct device_attribute *attr,
44 					  char *buf)
45 {
46 	struct drm_device *ddev = dev_get_drvdata(dev);
47 	struct amdgpu_device *adev = drm_to_adev(ddev);
48 	struct ttm_resource_manager *man;
49 
50 	man = ttm_manager_type(&adev->mman.bdev, AMDGPU_PL_PREEMPT);
51 	return sysfs_emit(buf, "%llu\n", amdgpu_preempt_mgr_usage(man));
52 }
53 
54 static DEVICE_ATTR_RO(mem_info_preempt_used);
55 
56 /**
57  * amdgpu_preempt_mgr_new - allocate a new node
58  *
59  * @man: TTM memory type manager
60  * @tbo: TTM BO we need this range for
61  * @place: placement flags and restrictions
62  * @res: TTM memory object
63  *
64  * Dummy, just count the space used without allocating resources or any limit.
65  */
66 static int amdgpu_preempt_mgr_new(struct ttm_resource_manager *man,
67 				  struct ttm_buffer_object *tbo,
68 				  const struct ttm_place *place,
69 				  struct ttm_resource **res)
70 {
71 	struct amdgpu_preempt_mgr *mgr = to_preempt_mgr(man);
72 
73 	*res = kzalloc(sizeof(**res), GFP_KERNEL);
74 	if (!*res)
75 		return -ENOMEM;
76 
77 	ttm_resource_init(tbo, place, *res);
78 	(*res)->start = AMDGPU_BO_INVALID_OFFSET;
79 
80 	atomic64_add((*res)->num_pages, &mgr->used);
81 	return 0;
82 }
83 
84 /**
85  * amdgpu_preempt_mgr_del - free ranges
86  *
87  * @man: TTM memory type manager
88  * @res: TTM memory object
89  *
90  * Free the allocated GTT again.
91  */
92 static void amdgpu_preempt_mgr_del(struct ttm_resource_manager *man,
93 				   struct ttm_resource *res)
94 {
95 	struct amdgpu_preempt_mgr *mgr = to_preempt_mgr(man);
96 
97 	atomic64_sub(res->num_pages, &mgr->used);
98 	kfree(res);
99 }
100 
101 /**
102  * amdgpu_preempt_mgr_usage - return usage of PREEMPT domain
103  *
104  * @man: TTM memory type manager
105  *
106  * Return how many bytes are used in the GTT domain
107  */
108 uint64_t amdgpu_preempt_mgr_usage(struct ttm_resource_manager *man)
109 {
110 	struct amdgpu_preempt_mgr *mgr = to_preempt_mgr(man);
111 	s64 result = atomic64_read(&mgr->used);
112 
113 	return (result > 0 ? result : 0) * PAGE_SIZE;
114 }
115 
116 /**
117  * amdgpu_preempt_mgr_debug - dump VRAM table
118  *
119  * @man: TTM memory type manager
120  * @printer: DRM printer to use
121  *
122  * Dump the table content using printk.
123  */
124 static void amdgpu_preempt_mgr_debug(struct ttm_resource_manager *man,
125 				     struct drm_printer *printer)
126 {
127 	struct amdgpu_preempt_mgr *mgr = to_preempt_mgr(man);
128 
129 	drm_printf(printer, "man size:%llu pages, preempt used:%lld pages\n",
130 		   man->size, (u64)atomic64_read(&mgr->used));
131 }
132 
133 static const struct ttm_resource_manager_func amdgpu_preempt_mgr_func = {
134 	.alloc = amdgpu_preempt_mgr_new,
135 	.free = amdgpu_preempt_mgr_del,
136 	.debug = amdgpu_preempt_mgr_debug
137 };
138 
139 /**
140  * amdgpu_preempt_mgr_init - init PREEMPT manager and DRM MM
141  *
142  * @adev: amdgpu_device pointer
143  *
144  * Allocate and initialize the GTT manager.
145  */
146 int amdgpu_preempt_mgr_init(struct amdgpu_device *adev)
147 {
148 	struct amdgpu_preempt_mgr *mgr = &adev->mman.preempt_mgr;
149 	struct ttm_resource_manager *man = &mgr->manager;
150 	int ret;
151 
152 	man->use_tt = true;
153 	man->func = &amdgpu_preempt_mgr_func;
154 
155 	ttm_resource_manager_init(man, (1 << 30));
156 
157 	atomic64_set(&mgr->used, 0);
158 
159 	ret = device_create_file(adev->dev, &dev_attr_mem_info_preempt_used);
160 	if (ret) {
161 		DRM_ERROR("Failed to create device file mem_info_preempt_used\n");
162 		return ret;
163 	}
164 
165 	ttm_set_driver_manager(&adev->mman.bdev, AMDGPU_PL_PREEMPT,
166 			       &mgr->manager);
167 	ttm_resource_manager_set_used(man, true);
168 	return 0;
169 }
170 
171 /**
172  * amdgpu_preempt_mgr_fini - free and destroy GTT manager
173  *
174  * @adev: amdgpu_device pointer
175  *
176  * Destroy and free the GTT manager, returns -EBUSY if ranges are still
177  * allocated inside it.
178  */
179 void amdgpu_preempt_mgr_fini(struct amdgpu_device *adev)
180 {
181 	struct amdgpu_preempt_mgr *mgr = &adev->mman.preempt_mgr;
182 	struct ttm_resource_manager *man = &mgr->manager;
183 	int ret;
184 
185 	ttm_resource_manager_set_used(man, false);
186 
187 	ret = ttm_resource_manager_evict_all(&adev->mman.bdev, man);
188 	if (ret)
189 		return;
190 
191 	device_remove_file(adev->dev, &dev_attr_mem_info_preempt_used);
192 
193 	ttm_resource_manager_cleanup(man);
194 	ttm_set_driver_manager(&adev->mman.bdev, AMDGPU_PL_PREEMPT, NULL);
195 }
196